With the release of Iron Man 3 less than three weeks away, actor Robert Downey Jr. director Shane Black and producer Kevin Feige gave us a brief tutorial on the technology behind the Iron Man suits, specifically the newest iteration, the Mark 42. While most Iron Man fans know of Mark I to VII, this behind-the-scenes clip reveals there are actually 42 suits in all. Ever the tinker and perfectionist, the fictitious gazillionaire industrialist Tony Stark churn out suits after suits in his underground bunker. For a bit of realism, Robert Downey Jr. actually commented on the benefits of Mark 42 and the use of "subdermal implants" to call up the suit, all without the assistance of a script. See the video after the jump or catch Iron Man 3 in a theater near on May 3rd.